The suitability of Tl2Ba2CaCu2O8 (Tl-2212) and MgO for growing SIS trilayers by metal-organic chemical vapor deposition (MOCVD) is examined. Low temperature (500°C) epitaxial (100) MgO film growth on (110) LaAlO3, by MOCVD using Mg(dpm)2 (dpm=2,2,6,6-tetramethyl-3,5-heptanedionate) is demonstrated, Tl-2212 does not decompose under these MgO growth conditions, although decomposition occurs at lower O2 partial pressures, To form trilayer structures, BaCaCuO(F) films are first grown on (1 10) LaAlO3 by MOCVD using Ba(hfa)2·mep (hfa=1,1,1,5,5,5-hexafluoropentane-2,4-dionate; mep=2,5,8,11,14,17-hexaoxanonadecane), Ca(hfa)2 tet (tet=2,5,8,11,14-pentaoxapentadecane) and Cu(dpm)2 precursors and are then post-annealed in the presence of bulk Tl2Ba2CaCu2O8 to form Tl-2212. MgO is then deposited by MOCVD. Finally, a top TBCCO layer is grown by MOCVD and subsequent Tl2O anneal to complete the trilayer. Both of the TBCCO layers are highly oriented, while the MgO layers are largely polycrystalline due to the rough underlying Tl-2212. Both TBCCO layers are superconducting (Tc∼105 K).
|Number of pages||4|
|Journal||Journal of Alloys and Compounds|
|Publication status||Published - Apr 1997|
ASJC Scopus subject areas
- Metals and Alloys